• Title/Summary/Keyword: 하도 buffering

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Estimation of Virtual Flooding Area using Elevation Buffering (하도 buffering 기법을 이용한 가상 홍수범람지역 산정)

  • Yi, Yong-Kon;Koh, Deuk-Koo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.771-773
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    • 2007
  • 미국의 텍사스 A&M 대학의 Damon Holzer교수가 개발한 Elevation buffbyrise 프로그램을 이용하여 여주대교부근의 가상홍수범람지역을 산정하였다. 하도 buffering기법을 이용하여 얻어진 가상홍수범람지역은 제방의 홍수범람제어 기능과 물의 흐름특성을 고려하기 어렵기 때문에 홍수범람지역이 과도하게 산정되었을 것으로 판단되지만 단시간에 홍수범람피해지역을 추정할 수 있으므로 침수예상지역에 대한 주민대피계획을 수립하고 대처할 수 있을 것으로 판단된다.

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A Pilot Project to Measure Propagated Error in Buffering Process (버퍼링 과정에서의 오차전파 측정을 위한 선험 프로젝트 수행)

  • Yu, Ki-Yun
    • Journal of Korean Society for Geospatial Information Science
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    • v.9 no.2 s.18
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    • pp.17-27
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    • 2001
  • Buffering is one of the popular spatial analytical functions widely used in many proximity analyses. The buffeting inevitably entails a new polygon of specified edge that is simulated by rolling a ball around the buffering object. While buffering, the error on the buffering object propagates to the new buffered object. In this paper the error propagation behavior during the buffering operation is analyzed based on a pilot project for two different data models: polyline and spline curve. Thus, the error on the buffered objects are classified, mathematically defined, and measured. For measurements, the pilot project is designed and performed using a test site that is a lake boundary at Wisconsin, USA.

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Low Power Consumption Technology for Streaming Data Playback in the IPTV Set-top Box (IPTV 셋톱박스 환경에서 스트리밍 데이터 재생을 위한 전력 소모 감소 기법)

  • Go, Young-Wook;Yang, Jun-Sik;Kim, Deok-Hwan
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.47 no.1
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    • pp.30-40
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    • 2010
  • The hard disk is one of the most frequently used storage in IPTV sep-top box. It has large storage capacity and provides fast I/O speed compared to its price whereas it causes high power consumption due to mechanical characteristics of spindle motor. In order to play streaming data in the set-top box, spindle motor of hard disk keeps active mode and it causes high power consumption. In this paper, We propose an offset-buffering and multi-mode spin-down method to reduce power consumption for streaming data playback. The offset-buffering inspects the user's viewing pattern and performs buffering based on the analysis of viewing pattern. So, it can maintain the status of spindle motor as idle mode for long time. Besides, it can reduce power consumption by spinning down according to offset-buffer size. The experimental result shows that proposed offset-buffering and multi mode spin-down method is about 28.3% and 12.5% lower than the full-Buffering method in terms of the power consumption and spin-down frequency, respectively.

Suggestion the Rational Items with Comparison and Review for Designing of Buffering Retention Facility (완충저류시설 설계 시 고려사항 분석을 통한 합리적 항목 제시)

  • Ahn, Sang Hyun;Jung, Younghun;Kwak, Jaesang;Um, Myoung-Jin
    • Journal of Korean Society of Disaster and Security
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    • v.15 no.1
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    • pp.23-34
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    • 2022
  • Korea Government promotes the installation of buffering retention facility to protect the water environment and prevent the environmental contamination event by toxic materials. Although the buffering retention facility is very important to protect the natural environment through the retention of accidental pollution and initial runoff, much study has not been done to suggest the guide line for the design of the facility. In this study, we suggested the rational items for the design of buffering retention facility based on many experts after we investigated and compared the previous results of many design materials.

Mitigating the Side-effect of Starting New Session in Multimedia Streaming using Multi-zoned Disk (구역분할 디스크를 사용하는 멀티미디어 서버에서 새로운 세션 시작에 따른 스케줄링 지연 현상의 최소화)

  • Cho, Kyeong-Sun;Won, You-Jip;Shin, Il-Hoon;Koh, Kern
    • Journal of KIISE:Computer Systems and Theory
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    • v.31 no.8
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    • pp.445-452
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    • 2004
  • Zoning technology of disk improved the performance of disk subsystem with increase of storage capacity and average transfer bandwidth. SCAN disk scheduling with double buffering is used to utilize the performance of zoned disk in multimedia system. However, this method has a problem that generates jitter when the number of steams increases. In this article, we propose the novel approach, pre-buffering policy, to overcome this problem. Pre-buffering avoids jitter by buffering the lack of data before starting service, which is estimated from the current cycle length and the maximum cycle length. We can calculate cycle length, data sire needed in each cycle and the possible lack of data caused by the increase of the number of streams using the numerical model of disk subsystem. Pre-buffering can be applied for multimedia systems and contribute to provide clients with high quality service without jitter.

A Design of Buffering System Based on Slot Addressing and Reference Time for Multimedia Sewer (멀티미디어 서버를 위한 슬롯 어드레싱 및 재참조 시간 기반 버퍼링 시스템 설계)

  • 김진호;양종운;나인호
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.05a
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    • pp.269-274
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    • 2001
  • This paper is study of buffering system for multimedia server. We propose the scheme that increasing the performance of multimedia sever by using the buffer sharing scheme and slot addressing algorithm to maximize fixed buffer utilization. Also, we calculate reference time about a used block and next stream reuse that stram. As a result, we propose the buffering system satisfy the users request using the extra bandwidth that reducing multimedia server I/O.

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Effects of Fiber Sources on Ruminal pH, Buffering Capacity and Digestibility in Sheep (섬유소 공급원이 면양의 반추위 pH, Buffering Capacity 및 소화율에 미치는 영향)

  • Seo, In-Jun;Kim, Myeong-Hwa;Kim, Dong-Sik;Lee, Sang-Rak;Maeng, Won-Jai
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.25 no.3
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    • pp.177-184
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    • 2005
  • This study was conducted to study the effect of fiber sources on ruminal pH and buffering capacity and whole digestive tract digestibility with five ruminally fistulated sheep. Evaluated fiber sources were alfalfa hay cube (AHC), corn cob (CC), com silage (CS), cotton seed hull (CSH), peanut hull (PHL), rice straw (RS), and sugarcane bagasse (SCB). Sheep were fed consecutively a diet containing each tested fiber source $(45\%)$ with a corn-based concentrate diets $(55\%)$ during each experimental period. Ruminal pH showed no difference among fiber sources except the significantly lower pH at 8h (p<0.05) with RS (pH; 5.78) than those in other sources. Buffering capacity showed significant differences at 0h (p<0.05) and 2h (p<0.05) after feeding in CS compared to those from SCB and CC, while there was higher in PHL (p<0.01) at 12h post feeding except AHC than CC, CS, SCB, and RS. Dry matter digestibility was significantly higher in CS (p<0.001) than in other sources. Neutral detergent fiber digestibility was higher in CC, CS, CSH, and RS than other fiber sources (p<0.001). These results suggest that ruminal pH and buffering capacity and whole digestive track digestibility were significantly affected by fiber sources in ruminant diet, and, therefore, should be took those effects into account for TMR formulation.

Accelerated Convolution Image Processing by Using Look-Up Table and Overlap Region Buffering Method (Loop-Up Table과 필터 중첩영역 버퍼링 기법을 이용한 컨벌루션 영상처리 고속화)

  • Kim, Hyun-Woo;Kim, Min-Young
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.49 no.4
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    • pp.17-22
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    • 2012
  • Convolution filtering methods have been widely applied to various digital signal processing fields for image blurring, sharpening, edge detection, and noise reduction, etc. According to their application purpose, the filter mask size or shape and the mask value are selected in advance, and the designed filter is applied to input image for the convolution processing. In this paper, we proposed an image processing acceleration method for the convolution processing by using two-dimensional Look-up table (LUT) and overlap-region buffering technique. First, based on the fixed convolution mask value, the multiplication operation between 8 or 10 bit pixel values of the input image and the filter mask values is performed a priori, and the results memorized in LUT are referred during the convolution process. Second, based on symmetric structural characteristics of the convolution filters, inherent duplicated operation region is analysed, and the saved operation results in one step before in the predefined memory buffer is recalled and reused in current operation step. Through this buffering, unnecessary repeated filter operation on the same regions is minimized in sequential manner. As the proposed algorithms minimize the computational amount needed for the convolution operation, they work well under the operation environments utilizing embedded systems with limited computational resources or the environments of utilizing general personnel computers. A series of experiments under various situations verifies the effectiveness and usefulness of the proposed methods.

Chloride Threshold Value for Steel Corrosion considering Chemical Properties of Concrete (콘크리트의 화학적 특성을 고려한 철근 부식 임계 염소이온 농도)

  • Song, Ha-Won;Jung, Min-Sun;Ann, Ki Yong;Lee, Chang-Hong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.1A
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    • pp.75-84
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    • 2009
  • The present study assesses the chloride threshold level for corrosion of steel in concrete by examining the properties of four different binders used for blended concrete in terms of chloride binding, buffering of cement matrix to a pH fall and the corrosion behaviour. As binders, ordinary Portland cement (OPC), 30% pulverised fuel ash (PFA), 60% ground granulated blast furnace slag (GGBS) and 10% silica fume (SF) were used in a concrete mix. Testing for chloride binding was carried out using the water extraction method, the buffering of cement matrix was assessed by measuring the resistance to an artificial acidification of nitric acid, and the corrosion rate of steel in mortar with chlorides in cast was measured at 28 days using an anodic polarisation technique. Results show that the chloride binding capacity was much affected by $C_{3}A$ content and physical adsorption, and its order was 60% GGBS>30% PFA>OPC>10% SF. The buffering of cement matrix to a pH fall was varied with binder type and given values of the pH. From the result of corrosion test, it was found that the chloride threshold ranged 1.03, 0.65, 0.45 and 0.98% by weight of cement for OPC, 30% PFA, 60% GGBS and 10% SF respectively, assuming that corrosion starts at the corrosion rate of $0.1-0.2{\mu}A/cm^{2}$. The mole ratio of [$Cl^{-}$]:[$H^{+}$], as a new presentation of the chloride threshold, indicated the value of 0.008-0.009, irrespective of binder, which would be indicative of the inhibitive characteristic of binder.

The Spatial Characteristics of Transit-Poors in Urban Areas (대중교통서비스 취약계층의 공간적 분포 특성)

  • Kim, Jae-Ik;Kang, Seung-Kyu;Kwon, Jin-Hwi
    • Journal of the Korean Association of Geographic Information Studies
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    • v.11 no.2
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    • pp.1-12
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    • 2008
  • This paper identifies public transit-poors and derives spatial characteristics of the poors' distribution in an urban area by utilizing buffering analysis of geographic information systems and remote sensing techniques in the case of Daegu metropolitan city. Since special attention is given to elderlies, this study assigns three hundred meter buffer from bus/subway station as service boundary for elderlies. The results of this study tell us that 1) the transit-poors are concentrated on suburban and rural regions, 2) high proportions of the transit poors are elderlies with spatial variations in many regions, 3) the main housing type of the transit-poors is single detached house. We expect that this study can contribute to build an effective policy-making by showing essential technical processes and methods in identifying policy-need groups and their characteristics of spatial distribution.

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